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Max login attempts per ip address and reverse DNS lookup

1) Is there an easy way to blacklist an IP address after for instance, 4 invalid login attempts?


2) a long, long time ago, I thought I heard mercury would have reverse DNS lookup. I don't see it in 4.90.


Thanks for a great product for my one user email server. I think I've been running somewhat problem free for over 20yrs.


Jerry


1) Is there an easy way to blacklist an IP address after for instance, 4 invalid login attempts? 2) a long, long time ago, I thought I heard mercury would have reverse DNS lookup. I don't see it in 4.90. Thanks for a great product for my one user email server. I think I've been running somewhat problem free for over 20yrs. Jerry

1) You don't say what sort of login attempts these are, but assuming they are authentication attempts in MercuryS: have you tried setting 'Simplified Phishing Protection' in the compliance tab?


2) Yes, that would be a useful addition, and I am also looking forward to seeing that smile


paul


1) You don't say what sort of login attempts these are, but assuming they are authentication attempts in MercuryS: have you tried setting 'Simplified Phishing Protection' in the compliance tab? 2) Yes, that would be a useful addition, and I am also looking forward to seeing that ;) paul

I saw the phishing but it says it locks the account for 30 minutes. At that rate I would be locked all day unless there is an authorized way around the lock.


Yes, they are login/password phishing attempts.


I saw the phishing but it says it locks the account for 30 minutes. At that rate I would be locked all day unless there is an authorized way around the lock. Yes, they are login/password phishing attempts.

I have been away from Mercury for awhile but I remember this as a lock per offending IP address. When you set this, keep it in mind when configuring devices for access. An error in credentials will trigger the 30 minute lockout.


I have been away from Mercury for awhile but I remember this as a lock per offending IP address. When you set this, keep it in mind when configuring devices for access. An error in credentials will trigger the 30 minute lockout.

I saw the phishing but it says it locks the account for 30 minutes. At that rate I would be locked all day unless there is an authorized way around the lock.



Are you using any blocklist checks such as Spamhaus?


> I saw the phishing but it says it locks the account for 30 minutes. At that rate I would be locked all day unless there is an authorized way around the lock. Are you using any blocklist checks such as Spamhaus?
edited Aug 26 '22 at 5:12 pm

Yes, I have several blacklist sites but get very, very few hits on spamhaus, barracuda, etc. I haven't seen an address rejected by those sites in quite a while.


Yes, I have several blacklist sites but get very, very few hits on spamhaus, barracuda, etc. I haven't seen an address rejected by those sites in quite a while.

I put any attempted failed auth attempts on an ACL blacklist, but that isn't very practical if you getting a lot from different IP addresses.


My best advice is to ensure all your usernames and passwords are long and obscure - that reduces the chances of them being broken by the usual automated login attempts.


I put any attempted failed auth attempts on an ACL blacklist, but that isn't very practical if you getting a lot from different IP addresses. My best advice is to ensure all your usernames and passwords are long and obscure - that reduces the chances of them being broken by the usual automated login attempts.

Lastly, with regards to the temporary block, is there a way to lengthen it or even make the block permanent when triggered in the transaction filter? I looked in the ini file and didn't see anything.


I think my passwords are long enough and obscure, I also don't use them on any other site.


Thanks for the pointers. The block on the ehlo [127.0.0.1] had a very large impact on my problem.


Jerry


Lastly, with regards to the temporary block, is there a way to lengthen it or even make the block permanent when triggered in the transaction filter? I looked in the ini file and didn't see anything. I think my passwords are long enough and obscure, I also don't use them on any other site. Thanks for the pointers. The block on the ehlo [127.0.0.1] had a very large impact on my problem. Jerry

Lastly, with regards to the temporary block, is there a way to lengthen it or even make the block permanent when triggered in the transaction filter? I looked in the ini file and didn't see anything.


I think my passwords are long enough and obscure, I also don't use them on any other site.


Thanks for the pointers. The block on the ehlo [127.0.0.1] had a very large impact on my problem.


Jerry


Lastly, with regards to the temporary block, is there a way to lengthen it or even make the block permanent when triggered in the transaction filter? I looked in the ini file and didn't see anything. I think my passwords are long enough and obscure, I also don't use them on any other site. Thanks for the pointers. The block on the ehlo [127.0.0.1] had a very large impact on my problem. Jerry

The built-in blacklist isn't configurable, but you could try using my SmtpEvt daemon to get some more options. It can do automatic Spamhaus lookups as well if desired.


The built-in blacklist isn't configurable, but you could try using my [SmtpEvt daemon](http://downloads.serieguide.se/SmtpEvt.zip) to get some more options. It can do automatic Spamhaus lookups as well if desired.

me again. One thing that was never cleared-up, simplified phishing? Does that lock the account completely or just for the offending IP address?


Example:


login CNCjerry badpass from 46.148.40.70
login CNCjerry badpass from 46.148.40.70
login CNCjerry badpass from 46.148.40.70
account locked or only locked from 46.148.40.70?


then immediately after account is locked:
login CNCjerry goodpass from 192.168.1.1 can this address login?


I've been getting hit by Iran on my two mail servers, only one is Mercury. There seems to be 5 servers in this botnet. They hit me about every 5 seconds, maybe more frequently. The log file hits 100meg in two months, for instance. So when I see it happening, and I don't check that often, i deny the entire botsubnet in an ACL on a 10Gig switch that feeds the server. Since September I've had to add about 15 addresses to the ACL, not a big hassle. When I add them everything settles down. By the way graywall really made a difference.


I can probably do this with an ACL, but is there a way to only allow logins to the mail server (authorized users) from a specific IP address range? For instance, my local subnet and then addresses on my cell network (if that is practical). If not, I think I'll figure out a way on my router.


Thanks, nothing but compliments from me. I've had so few issues for the past 21yrs, I think, I've used it.


Jerry


me again. One thing that was never cleared-up, simplified phishing? Does that lock the account completely or just for the offending IP address? Example: login CNCjerry badpass from 46.148.40.70 login CNCjerry badpass from 46.148.40.70 login CNCjerry badpass from 46.148.40.70 account locked or only locked from 46.148.40.70? then immediately after account is locked: login CNCjerry goodpass from 192.168.1.1 can this address login? I've been getting hit by Iran on my two mail servers, only one is Mercury. There seems to be 5 servers in this botnet. They hit me about every 5 seconds, maybe more frequently. The log file hits 100meg in two months, for instance. So when I see it happening, and I don't check that often, i deny the entire botsubnet in an ACL on a 10Gig switch that feeds the server. Since September I've had to add about 15 addresses to the ACL, not a big hassle. When I add them everything settles down. By the way graywall really made a difference. I can probably do this with an ACL, but is there a way to only allow logins to the mail server (authorized users) from a specific IP address range? For instance, my local subnet and then addresses on my cell network (if that is practical). If not, I think I'll figure out a way on my router. Thanks, nothing but compliments from me. I've had so few issues for the past 21yrs, I think, I've used it. Jerry
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